succd: Improve error messages

succbone/succd/modbus.go

@@ -101,11 +101,6 @@ func (d *daemon) modbusUpdate() {
 		// TODO: Input mapping goes here
 	}
 
-	// We must wait between reading and writing to the -KEC1 relay board
-	// because otherwise it chokes and times out the write registers
-	// command.
-	time.Sleep(time.Millisecond * 10)
-
 	// KFA1-KFA8
 	var relayState [8]bool
 	d.mu.Lock()
@@ -140,7 +135,7 @@ func (d *daemon) modbusUpdate() {
 
 	err = d.modbusClient.WriteRegisters(0x01, registerValuesKEC1[:])
 	if err != nil {
-		klog.Warningf("error while updating registers %v", err)
+		klog.Warningf("error while writing updated relay values to KEC1 %v", err)
 	}
 }